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92-P: Identification of a novel HLA*A680202 allele by sequence-based typing in an African American individual
Abstracts
S53
92-P
IDENTIFICATION OF A NOVEL HLA*A680202 ALLELE BY SEQUENCE-BASED TYPING IN AN AFRICAN AMERICAN INDIVIDUAL. Andrew L. Lobashevsky, Youri A. Serov, Grace A. Hommel-Berrey. Medicine, HLA Laboratory, Indiana University, Indianapolis, IN, USA. Aim: HLA-A*680202 is the name of a novel HLA-A allele identified in our laboratory during typing of an African American recipient. SSOP and SSP typing methods detected A*02xx/6901 and A*0260/6802 allele combinations respectively. Patient’s mother typing at A locus was reported as A*0260/32xx. Other family members were not available. Methods: Subsequent SBT using 3100 Genetic Analyzer and the AlleleSEQR HLA-A and SBTexcellerator HLA-A kits resulted to the following typing A*0260/A*68020101, 68020102, 68020103. DNA sequence analysis of exons 2, 3 and 4 with Assign SBT 3.5 software (Conexio Genomics, Australia) showed inconclusive HLA-A typing (no zero mismatch allelic combinations). Results: A new A*6802 allele was suggested at this time point. The further investigation consisted of subcloning (nine clones total) (QIAGEN® PCR cloningPlus Kit) of three PCR products generated by independent amplifications of full length of HLA-A locus (six exons and 3’UTR). The sequence analysis of the inserts confirmed that novel A*68NEW allele differs from the A*6802 by one nucleotide replacement at position 618 (ACG 3 ACT, codon 182). Conclusions: This substitution did not lead to an amino acid exchange of threonine in the mature protein. The name A*680202 has been officially assigned by the WHO Nomenclature Committee in October 2007.The allele HLA-A*680202 has the GenBank/EMBL Nucleotide Sequence Database accession number EU189866 and the IMGT/HLA Database accession number HWS10005045.
93-P
POLYMORPHISMS IN THE TNF-238 AND -308 PROMOTER REGION IN BRAZILIAN PATIENTS WITH EARLY-ONSET PSORIASIS. Renata F. Magalhaes,1 Ana C. Biral,2 Joa˜o A. Pancoto,3 Eduardo A. Donadi,3 Maria Helena S. Kraemer.2 1Dermatology, Faculty of Medical Science, Campinas, Sao Paulo, Brazil; 2Immunogenetic Transplant Laboratory, Department of Clinical Pathology; Faculty of Medical Science, University of Campinas, Campinas, Sao Paulo, Brazil; 3Immunogenetic Laboratory, University of Sao Paulo, Ribeirao Preto, Ribeirao Preto, Sao Paulo, Brazil. Aim: Psoriasis is a chronic inflammatory dermatosis around 2.5% of the Brazilian population. Polymorphisms in the TNF promoter region, especially replacement of guanine with adenine in positions -238 and -308, are related to different genotypes. There is higher TNF production and higher genetic risk in Caucasoid populations, not found in Japanese populations. This study was to evaluate whether polymorphisms in the TNF promoter region are genetic risk factors for the occurrence of psoriasis. Methods: Fifty-one patients who had disease onset up to 18 years of age and 50 controls were studied. The TNF promoter genes polymorphism was assessed by DNA/PCR/SSP, concerning the presence of single nucleotide polymorphism (SNP) -308A/G and -238A/G. Overall allele frequencies were estimated by Fisher test. Results: In the TNF-238 position were found, in patients and controls, GG genotype in 35 (70.0%) and 37 (72.6%), GA in 15 (30%) and 14 (27.4%) respectively, and AA in none of the cases. In the TNFA-308 position, the GG genotype was found in 43 patients (86%) and 49 controls (96%), the GA genotype in 7 (15,7%) patients and 2 (4%) controls and AA in none of the cases. No statistical difference was observed between the patient and the control groups in this study. Conclusions: These data suggest that polymorphism of the TNF promoter region, in brazilian patients with early onset psoriasis, would not be the psoriasis genetic risk factor, and encourages future investigations.
S53
92-P
IDENTIFICATION OF A NOVEL HLA*A680202 ALLELE BY SEQUENCE-BASED TYPING IN AN AFRICAN AMERICAN INDIVIDUAL. Andrew L. Lobashevsky, Youri A. Serov, Grace A. Hommel-Berrey. Medicine, HLA Laboratory, Indiana University, Indianapolis, IN, USA. Aim: HLA-A*680202 is the name of a novel HLA-A allele identified in our laboratory during typing of an African American recipient. SSOP and SSP typing methods detected A*02xx/6901 and A*0260/6802 allele combinations respectively. Patient’s mother typing at A locus was reported as A*0260/32xx. Other family members were not available. Methods: Subsequent SBT using 3100 Genetic Analyzer and the AlleleSEQR HLA-A and SBTexcellerator HLA-A kits resulted to the following typing A*0260/A*68020101, 68020102, 68020103. DNA sequence analysis of exons 2, 3 and 4 with Assign SBT 3.5 software (Conexio Genomics, Australia) showed inconclusive HLA-A typing (no zero mismatch allelic combinations). Results: A new A*6802 allele was suggested at this time point. The further investigation consisted of subcloning (nine clones total) (QIAGEN® PCR cloningPlus Kit) of three PCR products generated by independent amplifications of full length of HLA-A locus (six exons and 3’UTR). The sequence analysis of the inserts confirmed that novel A*68NEW allele differs from the A*6802 by one nucleotide replacement at position 618 (ACG 3 ACT, codon 182). Conclusions: This substitution did not lead to an amino acid exchange of threonine in the mature protein. The name A*680202 has been officially assigned by the WHO Nomenclature Committee in October 2007.The allele HLA-A*680202 has the GenBank/EMBL Nucleotide Sequence Database accession number EU189866 and the IMGT/HLA Database accession number HWS10005045.
93-P
POLYMORPHISMS IN THE TNF-238 AND -308 PROMOTER REGION IN BRAZILIAN PATIENTS WITH EARLY-ONSET PSORIASIS. Renata F. Magalhaes,1 Ana C. Biral,2 Joa˜o A. Pancoto,3 Eduardo A. Donadi,3 Maria Helena S. Kraemer.2 1Dermatology, Faculty of Medical Science, Campinas, Sao Paulo, Brazil; 2Immunogenetic Transplant Laboratory, Department of Clinical Pathology; Faculty of Medical Science, University of Campinas, Campinas, Sao Paulo, Brazil; 3Immunogenetic Laboratory, University of Sao Paulo, Ribeirao Preto, Ribeirao Preto, Sao Paulo, Brazil. Aim: Psoriasis is a chronic inflammatory dermatosis around 2.5% of the Brazilian population. Polymorphisms in the TNF promoter region, especially replacement of guanine with adenine in positions -238 and -308, are related to different genotypes. There is higher TNF production and higher genetic risk in Caucasoid populations, not found in Japanese populations. This study was to evaluate whether polymorphisms in the TNF promoter region are genetic risk factors for the occurrence of psoriasis. Methods: Fifty-one patients who had disease onset up to 18 years of age and 50 controls were studied. The TNF promoter genes polymorphism was assessed by DNA/PCR/SSP, concerning the presence of single nucleotide polymorphism (SNP) -308A/G and -238A/G. Overall allele frequencies were estimated by Fisher test. Results: In the TNF-238 position were found, in patients and controls, GG genotype in 35 (70.0%) and 37 (72.6%), GA in 15 (30%) and 14 (27.4%) respectively, and AA in none of the cases. In the TNFA-308 position, the GG genotype was found in 43 patients (86%) and 49 controls (96%), the GA genotype in 7 (15,7%) patients and 2 (4%) controls and AA in none of the cases. No statistical difference was observed between the patient and the control groups in this study. Conclusions: These data suggest that polymorphism of the TNF promoter region, in brazilian patients with early onset psoriasis, would not be the psoriasis genetic risk factor, and encourages future investigations.